The answerphone message is a lively elderly woman’s voice telling me she and her husband are out looking for the pot of gold at the end of the rainbow and if they find it, and if I leave a message, they will share. I laugh out loud; it seems somebody may have taken this literally. It’s her husband I’m after, Louis Christian, a retired oil company geologist who lives in Dallas, and a map maker with long experience in the Middle East. In the spring of 1998 the United States Geological Survey called to ask him to produce something on Iraq. His new maps would not tell the Marine Corps how to get to Baghdad, but may have everything to do with the reason they went. These were geological, subsurface structural maps, showing the thickness and types of rock at various depths, and essential for trying to calculate how much oil might be present. Louis drew them by hand, using information trawled from obscure technical papers in a dozen different languages, and charged a decent whack. That’s his business. Over the next 18 months he would deliver half a dozen. The USGS needed them to complete an assessment of Iraq’s potential oil resources. It was part of a wider assessment of the whole world they were conducting at the time, to be published in 2000. Just routine, apparently. Which makes it all the more interesting when you find out who paid for it…

Chapter 2: Dangerous Curves

The man who exposed the oil industry’s dirty little secret half a century ago was an irascible but brilliant Texan oil geologist called Marion King Hubbert. the BBC’s tape vaults in London there exists a short clip of him recorded in 1973, explaining the birth of his theory in the mid-1950s. Filmed at an easel with some hand-drawn graphs, Hubbert drawls “Common expression was ‘it wouldn’t happen in my lifetime, and my grandchildren could worry ’bout oil. I don’t have to'”.

On film Hubbert is a kindly looking old man, but according to Professor Kenneth Deffeyes who worked for him at the Shell research laboratory in Houston and became a lifelong friend, he was fearsome: “He could be spectacularly nasty”. Leaning back in his favourite recliner at home in Princeton, hands clasped on belly, Deffeyes recounts a typical incident during a lecture given at Shell by a guest speaker, when Hubbert spotted an error, calculated the correction in his head, and demolished the hapless lecturer from the back of the hall. “You didn’t want to make a mistake with Hubbert in the audience”.

Today Hubbert is largely remembered for his most famous theory, but his interests were broad and his scientific achievements formidable. In 1937 he solved a longstanding geological mystery by demonstrating mathematically how even the hardest rocks in the earth’s crust would flow like soft clays if subjected to immense pressure. In 1959 he helped solve another stubborn puzzle, explaining the mechanism behind the displacement of huge blocks of rock, known to geologists as overthrust faults. He was elected to the National Academy of Sciences in 1955, and in his later years became a professor at both Stanford and Berkeley.

In 1956 Hubbert did something even more significant, by publishing a new method for predicting when oil production in any given region would reach a peak, and then slip into terminal decline. The paper was based on ideas that he had evidently been worrying away at since the 1930s, but it seems it was not until the mid 1950s that he felt he had the data to launch his theory on the world.

The story of Hubbert and his 1956 paper is usually told like this: 1) in 1956 he predicted that US oil production would begin to fall in 1970, 2) it did, and 3) the end of the world is nigh. But this is a truncated parody that completely fails to reflect Hubbert’s real achievement. The story of how he developed his forecasting techniques during a decade-long running battle with his detractors illuminates a great deal about attitudes towards oil depletion in the industry and the geological establishment, and remains instructive today….

Chapter 5: Last Oil Shock, First Principles

I find a frivolous but striking image of our utter oil dependency in Galveston Bay, the broad and sheltered inlet on the Texas Gulf coast that funnels tankers into the Houston Ship Channel and the refineries that line its banks all the way up to the city, forty miles inland. Just after sunrise one steamy late September morning I am hammering north in tiny flat-bottomed Boston whaler with three middle-aged men who have taken the day off work to pursue their grand obsession. After about fifteen minutes we reach the buoy that tells them we’re where we need to be, the skipper James Fulbright cuts the engine, and we wait.

John, whose weathered face and long blond hair doesn’t quite square with his career in property management, scans the horizon through heavy yellow binoculars. We are a couple of miles out in the bay, but further still from the open sea, and sheltered from the choppy Gulf of Mexico by the sandbar of Galveston. Early morning sun glances off the surface of the murky green water slapping gently against the boat. The two surfboards jammed between the hull and the wheel-house seem oddly superfluous. Peter, a shaven-headed lieutenant in the local Sheriff’s Department, investigates the ice-box. James takes in some rays. I fiddle with my camera.

Finally, John spots what we’ve all been waiting for: “Here comes the motherlode”, he drawls in his thick Texan accent, “snub nosed and low in the water!” A heavily laden oil tanker has just rounded the point and is steaming fast in our direction. Quickly they slip into a well-rehearsed routine. John takes the wheel and puts the boat – which has drifted – back in position. The other two toss the surfboards over the side and dive in after them. As the 800 foot carrier Isabella draws level, the swell generated by her 105,000 deadweight tonnes hits the shallows and rears up to create a wave. Paddling hard to catch it, moments later Peter and James are on their feet and surfing. And unlike the beach – where a surfer’s ecstasy is measured in seconds – here they’re still riding two miles, and ten minutes later, as the tanker wave just keeps rolling over the shoals. Their all-time record is 4 ½ nautical miles in 22 ½ minutes. “It’s a real leg cramper”, James tells me afterwards, “you’re totally spent physically and mentally. It’s insane!”

It took Fulbright, a board shaper and documentary film maker from Galveston, years of patient research to find the exact locations out in the bay where the tanker waves form – weekends spent drinking with gruff old shrimp fishermen, poring over navigational charts, and out in his boat – and I am expected to keep my mouth shut. The crew doesn’t only surf the bow waves of supertankers – car carriers, container ships, anything fast and heavy will do – but they describe their passion as ‘tanker love’ for a reason. “I hate to say it”, says James, “but I want more tankers. Bring it on!”

Chapter 7: The Riddle of the OPEC Sands

The oil ministers must love the power trip. Whenever OPEC convenes to set production quotas for the coming months the meeting attracts a caravan of news agency reporters and business correspondents from around the world. For forty-eight hours scores of journalists scheme and scramble to catch the delegates between negotiations, and to be the first to report every ministerial word. This cut-throat competition traditionally climaxes on the afternoon of the second day with a ritual humiliation of the journalists charmingly known as the ‘gang bang’.

The sign perched on a brass stand in the lobby of the Intercontinental Hotel in Vienna reading ‘OPEC Press Corner’ was superfluous by the time I arrived. There was no mistaking the profession of the people idling watchfully among the laptops and dead coffee cups. The pregnant ashtrays suggested they had been there for some time. “We’re waiting for Iran and they’re late”, explained Reuters energy correspondent Barbara Lewis, with one eye on the main entrance. Everybody twitched as a pony-tailed television cameraman headed outside, then relaxed a little as he turned, grinning, and held up a cigarette to explain his intention. But journalists began to gravitate towards the revolving door anyway, just in case.

When the Iranian oil minister Bijan Zanganeh finally walked in, I glimpsed him for only a second before he was engulfed by a scrum of reporters shoving tape recorders in his face and lobbing questions. TV crews held their 20-pound cameras precariously at arms length over the heads of the rest, and flashlights popped like automatic fire. The scrum crabbed its way slowly across the lobby as journalists with Dictaphones in one hand and mobiles in the other relayed each vital phrase back to their newsdesks, and fur-clad Viennese ladies looked on bewildered. By the time the minister made it to the lifts, the whole crush had turned 180 degrees in unison and tipped over the OPEC Press Corner sign in the process, not that anybody noticed. By the time the minister made it back to his suite the snap headline on the Reuters newswire read: IRAN WORRIED ABOUT LEVEL OF OPEC COMPLIANCE ON QUOTAS.

After another two hours’ hanging around, a similar mobbing of the Nigerian Presidential Advisor on Petroleum, Edmund Daukoru, yielded: NIGERIA SAYS NOT TOO MUCH WORRIED ABOUT Q2 OIL DEMAND. To the civilian such esoteric comments may not sound desperately important, but any hint of a change in the future level of OPEC oil production is critical for the oil price. “One word from a minister can move the market”, Barbara Lewis explained, “and there’s a lot of money at stake”. OPEC members do, after all, account for some 40% of daily oil production, and claim to control three quarters of the world’s remaining proved reserves…..